<template>
	<view class="next-tree">
		<view class="next-tree-view">
			<scroll-view class="next-tree-view-sc" :scroll-y="true">
				<block v-for="(item, index) in treeList" :key="index">
					<view
						class="next-tree-item"
						:style="[
							{
								paddingLeft: item.rank * 15 + 'px',
								zIndex: item.rank * -1 + 50
							}
						]"
						:class="{
							border: border === true,
							show: item.show,
							last: item.lastRank,
							showchild: item.showChild,
							open: item.open
						}"
					>
						<view class="next-tree-label">
							<image
								@tap.stop="_treeItemTap(item, index)"
								class="next-tree-icon"
								:src="item.lastRank ? lastIcon : item.showChild ? currentIcon : defaultIcon"
							></image>
							<view class="name" hover-class="name-hover" @click="onconfirm(item)"> {{ item.name }}</view>
						</view>
					</view>
				</block>
			</scroll-view>
		</view>
	</view>
</template>

<script>
	export default {
		name: 'next-tree',
		props: {
			treeData: {
				type: Array,
				default: function () {
					return []
				}
			},
			valueKey: {
				type: String,
				default: 'id'
			},
			labelKey: {
				type: String,
				default: 'name'
			},
			childrenKey: {
				type: String,
				default: 'children'
			},
			title: {
				type: String,
				default: ''
			},
			multiple: {
				// 是否可以多选
				type: Boolean,
				default: false
				// default: true
			},
			selectParent: {
				//是否可以选父级
				type: Boolean,
				default: false
			},
			foldAll: {
				//折叠时关闭所有已经打开的子集，再次打开时需要一级一级打开
				type: Boolean,
				default: false
			},
			confirmColor: {
				// 确定按钮颜色
				type: String,
				default: '#f9ae3d' // #f9ae3d
			},
			cancelColor: {
				// 取消按钮颜色
				type: String,
				default: '' // #757575
			},
			titleColor: {
				// 标题颜色
				type: String,
				default: '' // #757575
			},
			currentIcon: {
				// 展开时候的ic
				type: String,
				default:
					''
			},
			defaultIcon: {
				// 折叠时候的ic
				type: String,
				default:
					''
			},
			lastIcon: {
				// 没有子集的ic
				type: String,
				default: ''
			},
			border: {
				// 是否有分割线
				type: Boolean,
				default: false
			}
		},
		data() {
			return {
				showTree: false,
				treeList: [],
				selectIndex: -1
			}
		},
		computed: {},
		methods: {
			_show() {
				this.showTree = true
			},
			_hide() {
				this.showTree = false
			},
			_cancel() {
				this._hide()
				this.$emit('cancel', '')
			},
			onconfirm(item) {
				this.$emit('confirm', item)
			},

			//扁平化树结构
			_renderTreeList(list = [], rank = 0, parentId = [], parents = []) {
				list.forEach((item) => {
					this.treeList.push({
						id: item[this.valueKey],
						name: item[this.labelKey],
						source: item,
						parentId, // 父级id数组
						parents, // 父级id数组
						rank, // 层级
						showChild: false, //子级是否显示
						open: false, //是否打开
						show: rank === 0, // 自身是否显示
						hideArr: [],
						orChecked: item.checked ? item.checked : false,
						checked: item.checked ? item.checked : false
					})
					if (Array.isArray(item[this.childrenKey]) && item[this.childrenKey].length > 0) {
						// console.log(item)
						let parentid = [...parentId],
							parentArr = [...parents],
							childrenid = []
						delete parentArr.children
						parentid.push(item[this.valueKey])
						parentArr.push({
							[this.valueKey]: item[this.valueKey],
							[this.labelKey]: item[this.labelKey]
						})
						this._renderTreeList(item[this.childrenKey], rank + 1, parentid, parentArr)
					} else {
						this.treeList[this.treeList.length - 1].lastRank = true
					}
				})
			},
			// 处理默认选择
			_defaultSelect() {
				this.treeList.forEach((v, i) => {
					if (v.checked) {
						this.treeList.forEach((v2, i2) => {
							if (v.parentId.toString().indexOf(v2.parentId.toString()) >= 0) {
								v2.show = true
								if (v.parentId.includes(v2.id)) {
									v2.showChild = true
									v2.open = true
								}
							}
						})
					}
				})
			},
			// 点击
			_treeItemTap(item, index) {
				if (item.lastRank === true) {
					//点击最后一级时触发事件
					this.treeList[index].checked = !this.treeList[index].checked
					this._fixMultiple(index)
					return
				}
				let list = this.treeList
				let id = item.id
				item.showChild = !item.showChild
				item.open = item.showChild ? true : !item.open
				list.forEach((childItem, i) => {
					if (item.showChild === false) {
						//隐藏所有子级
						if (!childItem.parentId.includes(id)) {
							return
						}
						if (!this.foldAll) {
							if (childItem.lastRank !== true && !childItem.open) {
								childItem.showChild = false
							}
							// 为隐藏的内容添加一个标记
							if (childItem.show) {
								childItem.hideArr[item.rank] = id
							}
						} else {
							if (childItem.lastRank !== true) {
								childItem.showChild = false
							}
						}
						childItem.show = false
					} else {
						// 打开子集
						if (childItem.parentId[childItem.parentId.length - 1] === id) {
							childItem.show = true
						}
						// 打开被隐藏的子集
						if (childItem.parentId.includes(id) && !this.foldAll) {
							// console.log(childItem.hideArr)
							if (childItem.hideArr[item.rank] === id) {
								childItem.show = true
								if (childItem.open && childItem.showChild) {
									childItem.showChild = true
								} else {
									childItem.showChild = false
								}
								childItem.hideArr[item.rank] = null
							}
						}
					}
				})
			},
			_treeItemSelect(item, index) {
				this.treeList[index].checked = !this.treeList[index].checked
				this._fixMultiple(index)
			},
			// 处理单选多选
			_fixMultiple(index) {
				if (!this.multiple) {
					// 如果是单选
					this.treeList.forEach((v, i) => {
						if (i != index) {
							this.treeList[i].checked = false
						} else {
							this.treeList[i].checked = true
						}
					})
				}
			},
			// 重置数据
			_reTreeList() {
				this.treeList.forEach((v, i) => {
					this.treeList[i].checked = v.orChecked
				})
			},
			_initTree(treeData = this.treeData) {
				this.treeList = []
				this._renderTreeList(treeData)
				this.$nextTick(() => {
					this._defaultSelect(treeData)
				})
			}
		},
		mounted() {
			this._initTree()
			this.$watch(
				() => this.treeData,
				(list) => {
					this._initTree(list)
				},
				{ deep: true, immediate: true }
			)
			this.$watch(
				() => [this.multiple, this.selectParent],
				() => {
					if (this.treeData.length) {
						this._reTreeList()
					}
				},
				{ deep: true, immediate: true }
			)
		}
	}
</script>

<style scoped>
	@import './style.css';
</style>
